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If A lies in second quadrant and 3tanA+4...

If `A` lies in second quadrant and `3tanA+4=0,` then the value of `2cotA-5cos A+sinA` is equal to

A

`-53//10`

B

`23//10`

C

`37//10`

D

`7//10`

Text Solution

Verified by Experts

The correct Answer is:
B

Here, `3tanA+4 = 0`
`=> tan A = -4/3.`
Now, `cot A = 1/tanA = -3/4`
As , `A` lies in second quadrant,
so, `sinA and cosecA` will be positive and other trigonometric functions will be negative.
Now, `tan A = -4/3`
`:. sec A = sqrt(1+(-4/3)^2) = -5/3`
`:. cosA = -3/5`
...
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